Prior art fuel controls for gas turbine engines have incorporated devices to enable an operator to manually position the main fuel metering valve and/or other control elements in the event of a failure in the automatic positioning system. Examples of manual control devices for electronic fuel controls are illustrated in U.S. Pat. Nos. 3,820,323; 4,077,203; and 4,302,931. In general, existing manual control devices have not been adapted to provide a nonlinear and adjustable Wf/P (fuel flow to compressor discharge pressure) schedule nor permitted manual control of the engine with the primary pilot power lever (PLA) operating in its normal quadrant. In addition, state of the art control devices have not provided a servo system with high force levels for positioning control elements whereby the PLA lever cannot be back driven either before or during actuation of the manual control device.